RU2251614C1 - Packer - Google Patents

Abstract

FIELD: oil production industry, particularly means for dividing an annular space and a tube space in flowing, gaslift, and beam wells.

SUBSTANCE: packer includes shaft with outer bored surface and bead and sealing members supported by the bead. Packer also has air cylinder forming annular cavity together with packer shaft. Cavity is connected with shaft interior through radial channels. Packer includes anchoring means. Lower anchoring means includes cone with slips and slip holder having bored inner orifice and threaded orifices. Lower anchoring means rests upon the bead and is connected to the shaft by shear screws installed in threaded orifices of slip holder. Shaft defines inner bored diameter and includes sliding bush located inside shaft. Shaft is provided with lower and upper grooves for sealing rings receiving and with outer grooves for cams and additional shear screws installation. Outer grooves are located between lower and upper ones. Slots are formed below bead on outer shaft surface for installing cams with limited radial travel. Threaded orifices are formed on outer shaft surface above inner groove thereof. Arranged into groove are additional shear screws to secure sliding bush in its initial position. The slip holder is freely installed on shaft or is spring-loaded. Support-moving bush is installed in inner bored orifice of slip holder between shear screws and cams. Support-moving bush is provided with facet formed from cam side and contacts with cams along mating facets upon shearing of shear screws. Free travel between cams and end of support-moving bush exceeds shear screw diameters to provide shearing thereof. When sliding bush is installed in fixed position cams extend above an outer shaft surface generator to provide displacement of support-moving bush and cut of shear screws. When sliding bush is located in operating position cams are located below outer shaft surface generator and move in radial direction into outer groove of sliding bush to provide free cam movement under support-moving bush and shear screws.

EFFECT: reduced number of lowering and lifting operations and breakdowns in the case or packer separation or during packer pulling out of well.

18 cl, 7 dwg

Description

The invention relates to the oil and gas industry, in particular to the technique of oil, gas and gas condensate, and can be used to separate annular and in-pipe spaces in a fountain, gas lift, pump or injection well with one or more production facilities (formations or interlayers).

A well-known hydraulic packer (A.S. No. 1788207, E 21 B 33/12, Bull. No. 2, 01/15/93), containing a hollow barrel with radial channels and an annular groove installed in the annular groove of the trunk with the possibility of axial movement of the upper anchor device in the form of a cone with dies, sealing elements in the form of cuffs installed on the barrel, a lower anchoring device in the form of a cone with dies and a die holder having a shank forming a hydraulic cylinder connected to the barrel through radial channels and a collet installed in the tail of the ram holder, fixing it relative to the barrel.

Known hydraulic reusable packer (RF Patent No. 2018628, E 21 B 33/12, Bull. No. 16, 08/30/94,), including a hollow barrel with radial channels and a coupling, a sealing element in the form of a cuff mounted on the barrel, located on the barrel with the possibility of movement and the upper cone connected with a locking element with dies and a ram holder of the upper anchor device, the lower anchor device installed under the sealing element in the form of a cone with rams and a lower ram holder, placed concentrically to the barrel g drotsilindr forming an annular cavity with the barrel, the barrel connected with the cavity through radial channels.

These packers have low reliability in operation under high thermodynamic conditions in the wells, since they are made without shear screws, which leads to spontaneous release of packers if the barrel moves sufficiently upward relative to the die when the pipe string is shortened.

A well-known hydraulic packer type PD-YAG (Catalog. Equipment for gas-lift operation of oil wells. Tsintikhimneftemash, M., 1991), including a hollow barrel with a machined diameter and a shoulder, sealing elements installed on it, a hydraulic cylinder forming an annular cavity associated with the barrel the barrel cavity through radial channels, the upper and lower anchoring devices, the upper of which is made in the form of an anchor, and the lower - in the form of a cone with dies and a die holder with an annular bore and threaded holes, made nnym to abut on the shoulder of the barrel and associated with the barrel screws shear to disrupt the packer installed in threaded holes plashkoderzhatelya. By design, a hydraulic packer installed in the well (for example, PD-YAG type, etc.) should be released by tightening its trunk upward with a load of 10-12 tons to ensure shear screws (M8 in the amount of 10 pieces) and move its trunk relative to the ram. However, in practice, after operating the hydraulic packer in the well for more than one year, in order to release it, in the main cases, a load of more than 20 tons will be required (in particular, due to the deposition of sand over its sealing elements), which often leads to breakage of the pipe string. Due to this reason, in some cases, when assembling the packer, smaller M8 shear screws are installed in smaller quantities to avoid complications when it is broken, which, in turn, can lead to spontaneous release of the packer during its landing and / or operation of the well. Also, its anchor works from external sub-packer pressure, due to which, when the packer is planted, spontaneous unpacking can occur.

The aim of the invention is to increase the reliability of the packer in the process of removing it from the well due to the possibility of releasing the packer either by mechanical tightening of the barrel under heavy load to cut the shear screws of the ram holder, or using cable technology and mechanical tightening of the barrel under light load, avoiding the cut of the shear screws of the ram holder as well as improving reliability during the installation of the packer in the well by eliminating the possibility of spontaneous release.

The positive effect of using the packer is to reduce the number of accidents during the failure and removal of packers from the wells and, accordingly, to overhaul them to eliminate accidents, as well as to increase its service life, well overhaul period and production of fluid.

This goal is achieved by the fact that for the reliability of the release of the packer, its barrel is made with a bored inner diameter, in which a sliding sleeve with lower and upper outer grooves for the o-rings is installed, and between them with outer grooves for the cams for the possibility of their radial movement and for additional shear screws. In this case, grooves are made below the collar on the bore outside diameter of the barrel, in which cams with a limited radial stroke are mounted on the outside diameter of the sliding sleeve and threaded holes are made on the outside outside diameter of the barrel over its inner groove, in which additional shear screws are installed to fix the initial position of the sliding bushings. In the bored inner diameter of the die holder between the shear screws and the cams, a support-movable sleeve with a chamfer on the cams side is installed, which contacts the cams along the mutual chamfers when the shear screws are cut.

In this case, the free travel between the cams and the end face of the supporting-movable sleeve is larger than the diameter of the shear screws for the possibility of their shearing. In the initial fixed position of the sliding sleeve, the cams protrude above the generatrix of the bore outer diameter of the barrel with the possibility of moving the support-movable sleeve and shear shears when the packer is broken by tightening and moving its barrel upward relative to the die. And when the sliding sleeve is in the working position, the cams are buried under the generatrix of the bore outer diameter of the barrel, radially moving into the outer groove of the sliding sleeve, ensuring their free passage under the support-movable sleeve and shear screws when the packer is released by mechanical or hydraulic action on the sliding sleeve and moving it from starting position, cutting off additional shear screws.

For manufacturability, the design of the packer, its trunk can be made of two (or more) parts, rigidly connected by a thread, while the bore of the inner diameter and the groove of the outer diameter of the barrel are made on the lower of its parts. Depending on the manufacturing technology of the packer, the grooves on the bore outside diameter of the barrel and, accordingly, the cams can be made transverse or longitudinal of the same geometric shape, and the cams are installed in the grooves from the inside or outside of the barrel and made in the form of a segment of a conical shape without beads or rectangular with beads on two sides in their lower part and chamfers on two sides in their upper part, or are made concentrically in the form of a conical or cylindrical shape. The sliding sleeve is made with a seating surface for landing a shock rope tool or a removable check valve, respectively, for its movement by mechanical or hydraulic action. The sliding sleeve, in the particular case, can be made with an elastic element in the form of a collet and, accordingly, one or two grooves for the collet petals are made in the barrel. The elastic element of the sliding sleeve before cutting the additional shear screws and fixing the sliding sleeve in the working position may have an inner diameter under the shock wire tool (sledgehammer) less than the inner diameter of the sliding sleeve itself, to allow the sliding sleeve to move down to the stop in the barrel ( a tool in the form of a sledgehammer passes down the barrel and gives information about the release of the packer). Also, the inner bore diameter of the sliding sleeve (without an elastic element) can be made larger than the inner diameter of the barrel under it, for the possibility of release (preload) and passage through the barrel of the shock rope tool in the form of a pusher after moving the sliding sleeve down to the stop in the barrel (also for information on releasing the packer). Cams can be made with a threaded hole for ease of installation during assembly of the packer. The outer grooves of the sliding sleeve for the cams and additional shear screws are made circular around its circumference. Two or three cam slots can be made on the barrel. For manufacturability, a stopper can be installed in the barrel under the sliding sleeve to stop it when moving down. The supporting-movable sleeve in the ram holder can be made cylindrical with an external groove or a groove for shear screws. Shear screws can be made with a shoulder to limit their downward movement when installed in the threaded holes of the ram holder. An external groove can be made on the barrel and a snap ring is mounted in it for stopping the ram holder. For the possibility, if necessary, of temporarily suspending the operation of the packer, the barrel is made with an additional bored inner diameter and a seating surface for installing a removable hollow tube (for example, using cable technology), hermetically disconnecting the radial channels of the barrel from its cavity. A locking device is installed below and above the sealing elements. To increase the reliability of the packer landing and prevent its spontaneous unpacking, the anchoring device above the sealing elements is made in the form of an anchor (for example, one or two parts), acting both from the internal and external pressure of the barrel. The dies of the anchor device are made with a straight, or sharp, or obtuse angle of the one-sided or two-sided direction of their teeth, and their hardness is greater than or equal to the hardness of the production casing of the descent packer for clutch reliability and eliminates the possibility of moving the packer both up and down.

Figure 1 shows a General view of the packer; figure 2 - anchor device packer with a sliding sleeve; figure 3 - anchor device packer with a sliding sleeve with an elastic element (option 1); figure 4 - anchor device packer with a sliding sleeve with an elastic element (option 2); figure 5 - anchor device packer with a sliding sleeve with a lower collar; figure 6 - anchor device of the packer with a supporting-movable sleeve in the ram holder; 7 is a section aa of figure 6.

The packer (Figs. 1-7) includes a barrel 1 (for example, of two interconnected parts) with a machined outer diameter 2 and a collar 3. Several sealing elements 4 and a hydraulic cylinder 5, which forms an annular cavity 6 with the barrel 1, are installed on the barrel 1 associated with the cavity 7 of the barrel 1 through the radial channels 8. Anchoring devices are also installed on the barrel 1, the upper of which is made in the form of an anchor 9 (in the particular case, its upper rams can operate from internal pressure, and the lower rams, on the contrary, from external sub-packer pressure ii) above the sealing elements 4 and the other below the sealing elements 4 in the form of a cone 10 with dies 11 (with one-sided or two-sided direction of their teeth) and a die holder 12 with a bore inner diameter 13 and threaded holes 14. The die holder 12 is made with the possibility of emphasis on collar 3 (in the particular case, on the snap split ring 15 in figure 3) and is connected with the barrel 1 by shear screws 16 (see figure 2) installed in the threaded holes 14. The barrel 1 has a bored inner diameter 17 with internal grooves 18, 19, 20 (see f city 2-4). At the same time, a sliding sleeve 21 is installed in the lower part of the barrel 1 (from below or from above) with the lower and upper outer grooves 22, 23 for the o-rings 24, and between them with the outer groove 25 for the cams (stops) 26 for their radial movement (see figure 2). The sliding sleeve 21 is made without or with an elastic element 27 (for example, in the form of a collet, etc.) and has an outer groove 28 for additional shear screws 29. Below the shoulder 3 on the machined outer diameter 2 of the barrel 1, grooves 30 are made (see Fig. 3 ), in which cams 26 are installed on the outer diameter of the sliding sleeve 21 with a limited radial stroke, without or with a threaded hole 31 for mounting. On the machined outer diameter 2 of the barrel 1, threaded holes 32 are made over its inner groove 20, in which additional shear screws 29 are installed to fix the sliding sleeve 21 in its initial position. In the bored inner diameter 13 of the die holder 12 (see FIG. 2), a movable sleeve 33 with a chamfer from the side of the cams 26 is installed between the shear screws 16 and the cams 26, which contacts the cams 26 along the mutual chamfers when the shear screws 16 are cut. the stroke between the cams 26 and the end face of the supporting-movable sleeve 33 is made larger than the diameter of the shear screws 16 to cut them off. In the inner diameter of the sliding sleeve 21 (see Fig. 2) or elastic element 27 (see Figs. 3, 4), a chamfer 34 or a collar 35 for a percussion wire tool, or a seating surface 36 for a removable check valve (for example, a gearbox type) , A, etc.) for its movement by mechanical or hydraulic action.

The elastic element 27 before cutting additional shear screws 29, moving and fixing it in the groove 18 (working position), in a particular case, is made with an inner diameter (under the percussion rope tool in the form of a sledge hammer) less than the inner diameter of the sliding sleeve 21. And also the inner diameter the collar 35 (figure 5) of the sliding sleeve 21 is made larger than the inner bore diameter 37 of the barrel 1 to enable the release of the impact rope tool in the form of a pusher with a decrease in its diameter. In the barrel 1 (see FIG. 6) below (or above) the sliding sleeve 21, a stopper 38 (for example, in the form of a split ring) can be installed to stop it when moving down or up. Also on the barrel 1 (see Fig. 3) an external groove 39 is made and a snap split ring 15 is mounted on it for stopping the ram holder 12.

The barrel 1 (see figure 1), in a particular case, is made with an additional bored inner diameter and a seating surface 40 below and above the radial channels 8 for installing a cable removable hollow tube (with upper and lower sealing cuffs), hermetically disconnecting the radial channels 8 barrel 1 from its cavity 7, in order to exclude, if necessary, the possibility of a packer being triggered (for example, when crimping a pipe string, planting and crimping another packer in a well, etc.).

The ram holder 12 (see FIG. 5) can be spring-loaded with a coil spring 41. In this case, the barrel 1 is equipped with a centralizer 42 from the bottom.

The packer works (see figure 1) as follows. It is lowered into the well to the required depth and excessive pressure is created in the pipe string to the pressure of its operation. Moreover, this pressure acts through the cavity 7 and the radial channels 8 in the cavity 6 of the hydraulic cylinder 5, which leads to the movement on one side of the cone 10 under the dies 11, and on the other hand to the pressing of the sealing elements 4, resulting in the dies 11 and the sealing cuffs 4 tightly abut against the wellbore, disconnect the hermetically pipe and annular spaces between themselves. During the operation of the anchor 9, its dies, triggered by internal pressure, do not allow the packer to move upward both during landing and during its operation (when pumping a working medium or producing fluid) in the well. And the dies of the anchor 9, triggered by external pressure (under the packer), exclude the possibility of moving the packer up only during its operation. Also, to exclude the possibility of moving the packer up (for example, when cold water is injected into the formation or the formation of the well) and spontaneously releasing it under thermobaric conditions, you can raise the pipe head with the pipe string to a small height (up to 1 m) from the crosspiece, and then install the packer, creating excess pressure in the cavity 7 of the barrel 1, and then lower the pipe head with the pipe string onto the crosspiece to create the necessary axial load (for example, 5-8 tons) on the packer from the weight of the pipe string, which eliminates the possibility of spontaneous failure (release) of the packer during well operation.

Packer can be released in two ways. In the first case (see figure 2) create a large interference fit of the barrel 1 by lifting the pipe string and provide shear shears 16 when moving the barrel 1 with cams 26 and through them the supporting-movable sleeve 33 relative to the dies 11. After shear shears 16 upward movement of the wellbore 1 releases the cone 10 from under the dies 11, which, accordingly, are released from contact with the wellbore. When this sealing elements 4 are returned from the deformed state to its original position, thereby ensuring the release of the packer.

In the second case (see Fig. 3), a check valve (for example, gearbox or A type) or a percussion instrument in the form of a sledgehammer or pusher is lowered into the well and the sliding sleeve 21 is moved hydraulically or mechanically in the barrel 1 from the initial position to working, cutting off additional shear screws 29 or moving the elastic element 27. After that, a slight interference is applied to the barrel 1 by lifting the pipe string, while the cams 26 are buried under the generatrix of the machined outer diameter 2 of the barrel 1, moving radially into the outer groove 25 sliding s sleeve 21 and provide a free passage for the cam supporting-movable sleeve shear screws 33 and 16. Next, barrel 1 with the movement also frees up cone 10 of a ram 11, which respectively are released from contact with the wellbore. Moreover, after hydraulically moving the sliding sleeve 21 with a check valve (for example, a gearbox or A, etc.) down to the stop in the barrel 1, in the particular case, a message may occur between the pipe and external cavities of the barrel 1 of the packer through radial channels (if any in stock) located between the sealing elements of the sliding sleeve 21 (see figure 6) to obtain information about the release of the packer due to the pressure drop in the barrel 1.

It should also be noted (see Fig. 1) that in order to temporarily exclude the possibility of the packer triggering when the pressure in the pipe string increases, a removable hollow blind plug is installed in the seating surface 40 of the barrel 1 (for example, using cable technology) and the cavity 6 of the hydraulic cylinder 5 is hermetically isolated from the cavity 7 of the barrel 1.

If there is a spring 41 (see Fig. 5), the packer can be reinstalled after cutting the shear screws 16, given that the ram holder 12 is in the upper position under the force of the spring 41. In this case, after the pressure inside the barrel 1 is created, the cone 10 moves downward provides contact dies 11 with the wellbore.

Claims (18)

1. A packer comprising a barrel with a machined outer diameter and a collar, sealing elements installed on it, a hydraulic cylinder forming an annular cavity with the barrel, connected to the barrel cavity through radial channels, anchoring devices, the lower of which consists of a cone with dies and a ram holder with a bore the inner diameter and threaded holes, made with the possibility of emphasis on the shoulder and connected with the barrel by shear screws installed in the threaded holes of the ram holder, characterized in that the barrel you filled with a bored inner diameter, in which a sliding sleeve with lower and upper outer grooves for sealing rings is installed, and between them with external grooves for cams for the possibility of their radial movement and for additional shear screws, while below the shoulder on a bore outer diameter of the barrel grooves in which cams with a limited radial stroke are installed on the outer diameter of the sliding sleeve and threaded holes are made on the bore outside diameter of the barrel above its inner a groove in which additional shear screws are installed to fix the initial position of the sliding sleeve, and in the bored inner diameter of the die holder between the shear screws and cams, a support-movable sleeve with a chamfer on the cams side is installed, which contacts the cams by mutual chamfers when shear screws are cut, when this free play between the cams and the end of the supporting-movable sleeve is larger than the diameter of the shear screws to be able to cut them, and with the initial fixed position of the sliding sleeve the cams protrude above the generatrix of the bore outer diameter of the barrel with the possibility of moving the supporting-movable sleeve and shear shears when the packer is broken by tightening and moving its barrel upward relative to the die, and when the sliding sleeve is in working position, the cams are buried under the generatrix of the bore outer diameter of the barrel, the outer groove of the sliding sleeve, ensuring their free passage under the movable sleeve and shear screws when releasing the packer by mechanical or hydraulic matic impact on the sliding sleeve and bring it to the starting position to the working position, cutting off the extra shear bolts. 2. The packer according to claim 1, characterized in that the barrel is made of at least two parts connected rigidly by a thread, while the bore of the inner diameter and the groove of the outer diameter of the barrel are made on the lower of its parts. 3. The packer according to claim 1, characterized in that the grooves on the bore outer diameter of the barrel and, accordingly, the cams are made transverse or longitudinal of the same geometric shape, and the cams are installed in the grooves from the inside or outside of the barrel and made in the form of a conical shape segment without collars or rectangular with flanges on both sides in their lower part and chamfers on both sides in their upper part or made concentrically in the form of a conical or cylindrical shape. 4. The packer according to claim 1, characterized in that the sliding sleeve is made with a seating surface for landing the shock rope tool or removable check valve, respectively, for its movement by mechanical or hydraulic action. 5. The packer according to claim 1, characterized in that the sliding sleeve is made with an elastic element in the form of a collet and, accordingly, at least one groove for the collet petals is made in the barrel. 6. The packer according to claim 5, characterized in that the elastic element of the sliding sleeve before cutting the additional shear screws and fixing the sliding sleeve in the working position has an inner diameter under the impact tool less than the inner diameter of the sliding sleeve. 7. The packer according to claim 1, characterized in that the inner bore diameter of the sliding sleeve is larger than the inner diameter of the barrel below it, so that it can be released and passed through the barrel of the percussion rope tool in the form of a pusher after moving the sliding sleeve down to the stop. 8. The packer according to claim 1, characterized in that the cams are made with a threaded hole for ease of installation. 9. The packer according to claim 1, characterized in that the outer grooves of the sliding sleeve for the cams and additional shear screws are made circular around its circumference. 10. The packer according to claim 1, characterized in that two or three grooves for the cams are made on the barrel. 11. The packer according to claim 1, characterized in that a stopper is installed in the barrel under the sliding sleeve to stop it when moving down. 12. The packer according to claim 1, characterized in that the support-movable sleeve in the ram holder is cylindrical with an external groove or groove for shear screws. 13. The packer according to claim 1, characterized in that the shear screws are made with a shoulder to limit their downward movement when installed in the threaded holes of the ram holder. 14. The packer according to claim 1, characterized in that an outer groove is made on the barrel and a snap ring is installed in it for stopping the ram holder. 15. The packer according to claim 1, characterized in that the barrel is made with an additional bored inner diameter and a seating surface for installing a removable hollow tube, hermetically disconnecting the radial channels of the barrel from its cavity. 16. The packer according to claim 1, characterized in that the anchoring device is installed below and above the sealing elements. 17. The packer according to claim 16, characterized in that the anchoring device above the sealing elements is made in the form of an anchor acting both from the internal and external pressure of the barrel. 18. The packer according to paragraph 1, characterized in that the dies of the anchoring device are made with a straight, or sharp, or obtuse angle of the one-sided or two-sided direction of their teeth, moreover, their hardness is greater than or equal to the hardness of the production casing of the descent packer to exclude the possibility of its movement as down so up.

Images